We investigate the phenomenon of non-recursive trade-offs between descriptional systems
in an abstract fashion. We aim at categorizing non-recursive trade-offs by bounds
on their growth rate, and show how to deduce such bounds in general. We also identify
criteria which, in the spirit of abstract language theory, allow us to deduce non-recursive
tradeoffs from effective closure properties of language families on the one hand, and
differences in the decidability status of basic decision problems on...